Gas and liquid contact apparatus



'Jall- 7, 1941 A. scHMALENBAcH 2,228,128

GAS AND LIQUID CONTACT APPARATUS Filed 'Jxxxly 2l, 1938 2 Sheets-Sheet lJan 7, 1941-` A. scHMALr-:NBACH 2,228,128

GAS AND LIQUID CONTACT APIARATUS Filed' July '21, 19:58 2 sheets-sheet 2Patented Jan. 7, 1941 -azzmzs eAs AND LIQUID coN'rAc'r APPARATUS dolfSchmalenbach, Essen, Germany, asslgnor,

by mesne assignments, to Koppers Company, y

- Pittsburgh, Pa., a corporation of Delaware Application July 21, 1938,Serial N0. 220,586 In Germany July 22, 1937 2 Claims. (Cl. 2651-22) 1The present invention relates to contrivances for bringing gaseous mediainto contact with liquids, forinstance for the washing of coaldistillation gases with wash oil in order to recover 5 valuableconstituents of the gas. and more particularly to washing contrivanceswhich comprise an essentially cylindrical casing subdivided by radialtransverse walls into several compartments in annular series which aretraversedby the liquid l and the gas in any desired manner. Theexpression washing contrivances" when used in this specication generallymeans contrivances for bringing gases into contact with liquids in thebroadest sense of the word, i. e. as well con- 15 trivances for washingout certain constituents l`from gases, as well as contrivances for.treating a liquid with a gas or gas mixture in'order to produce anydesirable reactions in the liquid.

, Washing contrivances of the above mentioned $0 type offer theadvantage that they require a rather small ground space and themanufacture of such washers is inexpensive. The disadvantagel of thewashers known hitherto which are fitted with a cylindrical casingsubdivided by 25 radial transverse walls consists in that the crosssection of the individual compartments of the washer greatly diEers fromthe circular or honey- -comb shape, which form is the most favourablefor theD uniform distribution of theliquid and of 80 the gas. l

The principal object of my present invention is to provide suchimprovements for the above mentioned washing contrivances withcylindrical casing and with several washing compartments I 35 formedtherein by radial transverse, walls that the cross section of theindividual compartments will practically be of honeycomb shape so as toobtain a good distribution of the washing liquid and of the gas to betreated over the Whole cross 40 area of the individual washer.compartment, thus ensuring a high eiiiciency of the washer.

Now, the leading feature of the present invention is that the radialtransverse wallsbetween the individual compartments of the washer com-46 prising an essentially cylindrical casing are divided or forkedvtowards the cylindrical outer shell of the casing in ,such a manner thatat the outer shell of the casing there are formed vertical channelsloian approximately triangular 50 cross-section which serve for thecirculation of the gas from one washer compartment into the adjoining orto another 'place of the washer.

t In the middle of the washer casing, I preferably arrange an innercylindrical or polygonal compartment coaxial with the cylindrical outershell of the casing'. The radial transverse walls of the washer with theforked walls extend from said inner circular or polygonal compartment.

The present invention, therefore, oil'e's the advantage that the deadcorners in the individual sector-like compartments of the hitherto-lmownwashers with cylindrical casing and radial transverse walls fittedtherein will be omitted. According to the invention it is possible tomake the cross section of the individual compartments practically ofhexagonal shape or honeycombshape by a suitable dimensioning of theforked portions of the transverse walls and possibly also the innercylindrical compartment of the casing so that a very eective and uniformdistribution ll of the gas and of the liquid is arrived at.

Further objects of' the invention ensure a higher enrichment of thewashing liquid with the constituents/ taken up from the gas thanformerly, as set forth in the following.

With the hitherto-known washing contrivances consisting of individualwashing towers, the delivery of the washing liquid to the individualwashers was generally made in counter-current to the direction of thegas stream so that the gas to be purified ows through the individualwashers one after the other, while the washing liquid j takes theopposite path.-

When adopting this known operating'method, it is necessary to deliverthe last washer of the 3o group always with such a quantity of freshliquid as is necessary for bringing it into contact with the gas to bepurified in an equal way, although a considerably smaller quantity offreshly added liquid would suihce for a complete purification of gas inthe nal washer. The regeneration of .this unnecessarily large quantityof washing liquid in turn requires a correspondingly large apparatus andincreases the steam consumption and the operating cost of the plant. o

To this end, a further object of the present invention consists in theprovision of means whereby only such a quantity of washing liquid needbedelivered lto the series of washer compartments as is necessary for thecomplete purifi- E cation of the gas. This idea of the invention may beadvantageously practiced in connection with the washing contrivances ofthe new type according to the invention, as described inthe followingdescription.

According to the invention, I arrange inthe radial partition .walls ofthe washer casing. near the bottom of same, suitable connecting openingswhich permit the liquid to flow from one washer compartment into theynext adjacent one, and I make such openings of such a cross-area thatthe quantity of liquid which flows through said openings into the nextcompartment will be equal tothe quantity of liquid freshly added to thewasher series. Furthermore I arrange the connection of the circulationpipe, which leads the liquid which collects upon the bottom of thevcompartment to the top of same, as near as possible to the openingprovided therefor in the radial partition Wall. In thisV way the liquidwhich ows through the said opening in the radial parl tition wall isprevented from flowing immediately through the adjacent compartment tclthe next succeeding one. The liquid is forced, however,

beforehand into the said connecting plpeand circulated in this waythrough the washer compartment together with a certain quantity of spentliquid collecting on the bottom of the washer compartment.

Furthermore the sector-like compartments formed by the radial partitionwalls are arranged in groups according to the invention so thatalternatively only the individual groups or all compartments may be usedforwashing. Ihis is advantageous in so far as it is now possible todisconnect certain washer compartments or groups of same, for instancein. order to clean out the apparatus o: to adapt the apparatus to asmaller capacity.

According to the invention, this problem is fa.- vourably solved in sucha way that a by-pass tted with a shut-oii means is provided at the gasexit of' a group of washer compartments so that l .the gas may bedischarged from the bly-pass or led through same into the nextcompartments.

With the above and other objects and features of my present invention inview, I will now describe a preferred embodiment of my invention on thelines of the accompanying drawings, in

Fig. 1 shows a vertical section through a washing contrivance on lineI--I of Fig. 2; Y

Fig. 2'shows a horizontal section through a washing contrivance on line2--2 of Fig. 1;

'45 Fig. 3 shows another form of construction according to the inventionlikewise in horizontal section and Fig. 4 nally shows on an enlargedscale a vertical section of a part of the washer.

The washer illustrated on the drawings comprises a substantiallycylindrical casing I built on av foundation 2. The casing is closedbelow by the bottom 3 and at the top by the cover 4. Co-axial with thecasing wall I, there is a central smaller casing 5 which likewise is ofavsubstantially cylindrical shape and connected with the bottom 3 andthe cover 4 in a gas tight manner.

From thewall 5 there extend to the outer wall,

radial partition walls 6 each of which fork against the casing wall Iinto two walls 6a, 6b forming the vertical and gas tight channels I2together with the casing wall I.

I'he washing liquid -is delivered to the separate washing compartmentsI0 which are tted with hurdles 9 or other suitable filling bodies,through the sprays 8 provided in the cover 4. The washing liquiddistributes over the hurdles 9 and flows downwards and ilnally collectsupon the Y bottom oieach compartmentA II. 'I'he gas from the washercompartments I0 is preferably led from below, thus coming into intimatecontact in counter-current with the washing liquid.

In the upper part, the gas ilows from the wash- 7'5' er compartments I0into one of the adjacent vert-he main Vdelivery pipeY II is led into thewesh tical channels I2, passes downwards therein and then enters anotherwasher compartment I0. In this way it is possible for'the gas to ilowthrough all the compartments II) of the washing contrivance one afterthe other. 5

It is advisable to provide a separate liquid circulation system for eachwashing compartment I0. The washing liquid accumulating on the bottom ofthe compartment is pumped through a suitable pipe line to the spray 8 orany other i0 suitable distributing device provided therefor at region ofthe cover of each compartment.

The paths taken by the gas and the liquid through the washingcontrivance are more fully explained in the following: 15

As shown in Fig. 2, the gas may flow through two groups of washercompartments. In this case the gas rst iiows from the main pipe line I I(Fig. 2) into the bottom of the triangular vertical channel I2 in whichis arranged a horizontal 20 partition wall I3 (Fig. 1) preventing thegas from flowing upwards. 'I'he channel I2 is connected below with thecompartment I0 through the opening I2A. The gas enters this compartmentIl) (see arrows a in Drawing 2) and flows up- 25 wards. After owingthrough the hurdles 9 or other suitable distributing means, the gasenters the next triangular channel I2a through which it passes downwardsto the next washer compariment IIla. From there, the gas passes through30 the channel I2b into the washer compartment Ib. The gas from thewasher compartment I 0b is delivered through an upper connecting openinginto the central cylindrical compartment 5a which .is separated fromthecompartment 5b 35 through the vertical partition wall 43. Thecompartments 5b and 5a are situated within the central cylindricalcasing part 5.

The gas in the compartment 5a flows downwards and then passes through a.lower connectilo ing opening I4 (Fig. 1) into the washer compartment Icwhich lies near the channel I2 through which the gas flows in at first.From that compartment IIJc the gas is sucked-off above into the p pipeI5 formed as a by-pass. The by-pass I5 45 is connected with a maindischarge pipe I 6 controlled by a shut-off valve 20, and similarly asto pipe I1 which is controlled by the shut-off valves 2|, 22. Betweenthe shut-01T valves 20,

. 2I is situated the connecting pipe line Ila lead- 5I) ing to thebottom of the channel I 2d.

Instead of withdrawing the gas from the pipe line I5 into the pipe lineI 6, it may also be led after a suitable reversal of the valves 20, 2|22 from the by-pass I5 through the connecting pipe "5'5 I'I, asindicated bythe arrows b (Fig. 2) into the washer compartments Ind,thence into the central compartment 5b, through the washer compartmentIIIe, channel .I2e, compartment IIif, channel I2f, compartment IIIg intothe channel ii() |211. pine line Ilia to the main collecting pipe I5.

If only one half of the washing contrivance is to be used, for instancefor the purpose of cleaning the other half, the gas introduced into gthe by-pass I5 m'ay be delivered through the t5 opened valve 20immediately into the discharge pipe line I6. In this event the valves2|, 20a

are shut on.

,y may be put into operationandY the other half may be shut-down. Thecontrivance may be operated in such a way that the valve 22 of theconnecting pipe line I'Iais opened and the gas from .Washercompartments.

compartments Ind, the central compartment lb, thewasher compartment I8e,I8! and Ilg and finally to the main collecting pipe I8. The second halfof the washing contrivance is then separated from the main pipe line Ilby means of the shut-olf valve 28 provided for in the connecting line24.

. It is advisable that the washing liquid flows in the oppositedirection through theV washer compartments as compared with the gaspath. The washing liquid flows to the compartment Illa through the pipe25 controlled by a valve 25a. The pipe 25 is connected with ya pipe line25 which slightly projects above the bottom of the washer into thewashercompartment Ilig up to near the liquid outlet 21.V The liquid is forcedthrough the pipe line 21a"by means of the pump 89 through the pipe I8 tothe spray 8 which is arranged at the top of the washer compartment. Inthe radial walls B separating the washer compartments there is arrangednear the bottom approximately in line with the end of the liquid inletpipe 26 an overow opening 28 through which flows a part of the washingliquid collecting upon the bottom of the washer compartment into thenext compartment. The liquid flowing through such an overflow 28 rstenters a small overflow pot '29 (Fig. 4) which reaches up to cover theoverow opening and which is opened above. To the bottom of the overflowpot 29 is connected thesuction main of the liquid circulation systembelonging to the washer compartment.

The liquid is, therefore, introduced into each washer compartment nearthe exit of the cire culating pipe, thus ensuring that the liquidflowingover fromone compartment to the next is caught directly bythe pump andtogether with a part of the liquid already accumulating on the bottom ofthe washer compartment it is circulated to the top of the washer.' Thisprocedure isrepeated in a suitable manner for all As may be seen fromthe drawings, the washing liquid enriched or spent, flows from everywasher compartment at a pointY which lies opposite the entrance of thewashing liquid into the compartment. The liquid inlet is furthermoresituated within a sort of seal which is arranged on the bottom ofthewasher compartment and consequently, the liquid entering the compartmentcannot mingle with the spent liquid running downwards through thehurdles and coilecting on the bottom of the compartment so that .theinflowing liquid does not'v flow acrossthe bottom into the nextcompartment thereafter.

The freshly admitted liquid is, instead, first recirculated in everywasher compartment before entering a next compartment, thus eifectih'g ahigh efiiciency of the washer. l

In this way only so much treshwashing liquid is addedithrough the pipe25 as necessaryfor the complete extraction of the gas. The wash ingliquid thus absorbs the largest possible quantity of constituents to beextracted from the gases.

After the ,washing liquid has passed through all the washer compartmentsone after the other, it leaves the washer compartment i8 through thepipe line 30.

In 'order tovbe able to shut off the washing liquid in a suitablemanner, if only one'y half of the washing contrivance is to be used, thetransition of the washing liquid around the partition vwall 6c (Figs. 2and 3) separating the two washer groups from one another takes place bya syphonlike pipe 8i (Fig. 4r) which is connected with the dischargepipe 88 by means f a three-way cock 32. By a reversal of the three-waycock82 the stream of liquid through the one or other washer group may bestopped which depends upon the group to be kept in operation and thewashing `liquid is only allowed to circulate through one group.

With the washing contrivance illustrated in Figs. 1 and 2, the centralcompartments 5a, 5b do not serve for the treatment of the gas. Fig. 3shows a construction in which the central compartment 5 is also filledwith hurdles and which serves for the pu'riflcation of the gas. The gasmay then flow through the various washer compartments as follows:l

The gasfrom the main gas pipe flows through the connecting piece 38 tothe bottom-of the vertical triangular channel 31, the top of which is'closecL 'Thence the gas ows in series to the compartments 8l, 34a, 34hinto the washer 'compartment 34e as shown by arrows C in Fig. 3.

From the washer 34e, the gas enters the vertical channel 81a above andfrom here it may be withdrawn through the pipe line 35 governed by thevalve 35a or as already illustrated in Figs. 2--1 similarly through thevertical pipe 88 downwards into the lower half of the triangular casingcompartment 31a and from here further on through the washer compartments38d, 88j, the central compartment 5 and the last. compartment 34g.Thence the gas enters the upper half of the triangular compartment 31 towhich the gas outlet pipe is connected (see arrows d in Fig. 3).

In this way the greatest variety of gases and also of the washing liquidis rendered possible. Instead of operating two washer groups accordingtothe method described in the in the flow foregoing it is alsopossibleto use several groups 40 tion on the lines of a preferredembodiment thereof, but my invention is not limited in allits aspects tothe model of carrying it out as described and shown', since theinvention may be variously embodied within the scope of the followingclaims.

I claim:

1. Gas and liquid contact apparatus comprising: a substantially annularcasing closed at bottom and top; radial partition walls arranged in thecasing between the inner and outer walls of the casing and connectedtherewith and with the bottom and top in a gastight manner to form anannular series. of Agas treating compartments; means for introducingliquid to the respective compartments -at` their upper parts; means forwithdrawing the liquid from the compartments at their lower parts; saidradial'partition walls being terminated in forked walls atto 4form withthe rest of the radial portions and f the inner and outer walls of theouter casing the compartments into chambers approximately" vring-like inhorizontal cross-section; the forked walls of each of the channelshaving anopenj ing at the top of one of the walls forming a:communication between the top of the channel and the top of one of thecompartments and having an opening at the bottom of the other wallintercommunicating the bottom of the channel and the bottom of theadjacent compartment for circulation of gas from each compartment to thenext into and out of each compartment at the outer wall of the annularcasing where the compartments are widest.

2. Gas and liquid contact apparatus comprising: a substantially annularseries of gas treating compartments with gas-tight radial partitionwalls between the compartments; vertical channels communicablyconnecting each compartment at its top with a next adjacent compartmentat its bottom for circulation of gas in series through the compartmentsupwardly through the respective compartments; wherein overow openingsare provided in the radial partition walls near the bottoms of thecompartments for 4overflow of liquid from the bottom of each compartmentto the bottom of the next, and wherein an overflow pot is provided ineach compartment bottom for receiving the liquid from the overow openingthereto and main-4

